Exchanger vapor generators



June 18, 957 I G. A. REHM 2,795,050 7 EXCHANGER VAPOR GENERATORS FiledApril 22, 1954 5 Sheets-Sheet l In We 72 Z02" 'as fav ./7. fiem June 18,1957 G. A. REHM EXCHANGER VAPOR GENERATORS 5 Sheets-Sheet 2 Filed April22. 1954 jnvenzor Jarfier & @arfer .itzarneys June 18, 1957 G. A. REHMEXCHANGER VAPOR GENERATORS 5 Sheets-Sheet 5 Filed April 22, 1954 U IInventor lfflllllfllfll Iflllllll!llflllflll mrflld Jzfarney June 18,1957 G. A. REHM 2,796,050

I EXCHANGER VAPOR GENERATORS Filed April 22, 1954 5 Sheets-Sheet 5uszaz/ A jikm United States Patent F EXCHAN GER VAPOR GENERATORS GustavA. Rehm, Springfield, Ill., assignor to Springfield Boiler Company,Springfield, 111., a corporation of Illi- IIOIS Application April 22,1954, Serial No. 424,991

3 Claims. (Cl. 122-32) heat; for example, the cooling jackets of aninternal combustion engine or the like.

A primary object of my invention is a steam generating unit designed andconstructed. to convert heat energy from a so-called contaminated sourceinto high pressure steam.

Another object of my invention is a unit of the above type adapted foruse with a heat exchanger fluid or coolant with one or more heatexchangers in combination with a steam drum.

Another object of my invention is a steam generating unit of the abovetype constructed and arranged for ease of access while having generallyheavy tube sheets and the like.

Other objects will appear from time to time in the ensuing specificationand drawings in which:

Figure 1 is a transverse sectional view of my steam generating unit;

Figure 2 is a longitudinal view of the unit shown in Figure 1, withparts omitted or broken away for clarity;

Figure 3 is a transverse sectional view, similar to Figure l, of amodified form of the steam generating unit shown in Figure 1;

Figure 4 is a side view of this modification; and

Figure 5 is a diagrammatic illustration of still a third form of myinvention.

In Figure 1, a steam generating unit is indicated generally at andincludes a horizontally disposed drum 12 with a plurality of generallyupright heat exchangers 14. The heat exchangers are arranged ingenerally symmetrical rows one or more deep, as shown in Figure 1, andone or more across as shown in Figure 2.

High pressure heated fluid, hereinafter referred to as the coolant, froma heat source is brought in through a suitable inlet main 16 anddischarged through an outlet main 18. The heat exchangers 14 are mountedgenerally upright on any suitable supporting structure, not shown..

Inlet pipes 20 extend inwardly as shown in Figures 1 and 2, and areconnected to the inlet main 16. Suitable inlet connections 22 join eachof the heat exchangers to one of the pipes 20 and outlet connections 24carry the coolant from the heat exchangers to outlet pipes 27 whichcarry the coolant to the outlet main 18. While I have shown onlythreesuch inlet and outlet pipes 20 and 27. serving six sets of heatexchangers, there could be six or,

Patented June 18, 1957 Ice 30 up through the heat exchanger and back tothe outlet portion 32.

Thus, the coolant will enter through the inlet main 16, will circulateinto the transverse inlet pipes 20, will flow through each of the inletpipes 22 to the inlet portions 30 in the bottom or side of the heatexchanger, and up through the heat exchanger tubes 34 and back to theoutlet portion 32 where it is discharged through the outlet pipes 24 tothe conduit 26 and back to the outlet main 18.

The interior of each of the heat exchangers is adapted to contain afluid, such as water or liquid metal or any other suitable liquid, up tothe level indicated in Figure 1. The water is drawn off through pipes 36to a transverse conduit 38, a group of which extend between the heatexchanger, as shown in Figure 2, and out to a longitudinal main 40. Adischarge pipe 42 carries the water to a pump 44 and is recirculatedthrough a supply pipe 46 to a longitudinal inlet main 48. This main hasa plurality of jets 50 adapted to inject water into a group oftransverse conduits 52 with venturi sections extending between the heatexchanger, as shown in Figure 2, connected to the lower end of the heatexchangers by pipes 56. Thus, a closed circulating system is formed witha conventional pump 46 circulating water drawn off at the top of theheat exchangers through the pipes 36 and returning itto the bottom ofthe heat exchanger through the pipes 56. Water carryover pipes 59 fromthe heat exchangers to the steam drum are provided, as required, tomaintain a water level in the heat exchangers and the drum.

The steam formed in each of the heat exchangers is carried to the steamdrum by a plurality of pipes 58 with appropriate valves, if valves aredesired. The top of the heat exchangers are provided with suitablemanholes and covers 57.

A suitable outlet 60 for steam is provided on the drum, and a feed watermake-up to the drum is provided through an inlet 62, the amount of waterbeing fed to the drum for make-up being regulated by a Valve 64controlled by an expansion tube 66. One end of the tube is connected tothe top of the drum through a pipe 68 while the other end is connectedto the steam drum below the water level by a pipe 70. If there is suddenincrease in the steam demand, a rapid withdrawal of stored steam isfollowed by a rapid drop in pressure, and a bubbling up of escapingsteamat a rapid rate. This raises the water level in the drum andcontracts the tube which decreases the valve opening. The decrease ofcold water feed input allows the boiler to steam at the required rate. Acontinued heavy steam demand gradually lowers the water level in theboiler tube, expanding the tube and opening the control valve 64 wideenough to pass through acquired flow.

The specific internal details of the steam drum 12 of themselves do notform a part of this invention and as an example only, reference is madeto U. S. Pat. No.

In Figure 3, I have shown a modified form of my invention, a lot of thedetails being the same as in Figures 1 and 2; for example, six heatexchangers are positioned transversely and arranged in four rows. Asteam drum 102 is positioned above the normal water level 104,

' each of the heat exchangers being connected at its top to the returnand inlet pipes so that natural circulation can take place, the degreeof forced circulation provided being regulated by a suitable valvesystem. The water inlet from thepump has branches 118 with jets 120which project water into a venturi section 122 in the branches 116. Asuitable steam outlet 124 is provided on the steam drum with one or morecondensate returns 126 connected to the bottom of the drum and to thefluid circulating system.

It should be noted that a water level is not maintained in the steamdrum and only steam alone is provided. One or more standpipes 128 areconnected to the steam drum by a lead 130' and to the water in the heatexchangers by'a pipe system 132. A suitable feed water make-up controlsystem similar to the one shown in Figures 1 and 2, is indicated at 134for regulating the amount of make-up water supplied to the systemthrough a pipe 136 from a suitable source 138. a

The coolant circulating system can be generally the same as shown inFigures 1 and 2.

In Figure 5, I have shown a modified form similar to Figures 1 and 2 andshowing one of the heat exchangers diagrammatically connected to thedrum. The exchanger 150 has a coolant inlet 152 and outlet 154 connectedto a chamber 156 in the bottom of the exchanger. The chamber is dividedinto two portions by a wall section 158, and the coolant is circulatedup through the fluid in the exchanger pipes 164). Steam is taken outofthe top of the exchanger through a suitable connector 162 toa steamdrum 164. The water circulating system includes the pipe 166 connectingthe top of the heat exchanger to the drum and the pipe 16% for returningfluid from the drum to the bottom of the heat exchanger. The steamoutlet is provided with a separator 169 which returns moisture to thefluid outlet flow in pipe 166 by a lead 170. The pipe 168 may beprovided with a forced circulation pump to augment the water circulationif desired, as in Figure l.

Make-up water and return condensate from a conventional turbinegenerator unit or the like is introduced into the drum from an inlet 171by a suitable pump or the like and is heated by the steam from the pipe162. The inlet or makeup water flows down over an internal structure inthe drum designated at 172 generally, the details of which are old andconventional as shown in U. S. Pat. No. 2,655,905. The heat exchanger159 is divided into a plurality of segments or sections. bottom section174-is generally cup-shaped and is welded to an intermediate section 176in a circular connection indicated generally at 178. The intermediatesection 176 has access openings 16th for inspection and repair. An

pipe 168 is connected to a section 134 which is welded at 186circumferentially to the intermediate section and.

to the main portion 188 of the heat exchanger at a circumferential weld199. A circular shield or baffle 191 is. provided to prevent theincoming water from damaging the tubes.

The use, operation, and function of my invention are as follows:

My invention is primarily usable with a heat source that contacts thefluid or coolant by circulating around it; for example, a chemicalreaction or process, an internal combustion engine, an electricalreaction or magnetic reaction, as the case may be, or any other type.The coolant circulating around the source could be heavy water, ordistilled water, a liquid metal, sodium, or the like. The coolant fromthe heat source will be at a very high pressure; for example, in onecase in the neighborhood of 2300 lbs. p. s. i.

The coolant cannot be used as the fluid to directly transfer the heat toa turbo-generator unit; Therefore, I have provided an intermediatetransfer unit so that the heat energy can be transferred from thecoolant to a more usable fluid; for example, water. To do this, thecoolant is circulated through a group or battery of heat exchangerswhich are constructed both to withstand the high pressures of. thecoolant and also to prevent intermingling of For example, the

4 the coolant and water so that the water will not become contaminated.With these heat exchangers, a conventional drum is connected in a closedcirculating system, be it a water drum or a steam drum, and heat energyin the form of steam is withdrawn from the drum and used in aturbo-generator or other unit.

While I have not shown other conventional details, it should beunderstood that conventional condensers and pumps could be used toreturn the condensed steam to the water circulating system.

The large rolled sections of metal shown in the lower part of theexchanger in Figure 5 are provided to withstand the high pressures inthe coolant.

The entire unit could be constructed as follows:

One steam drum, such as in Figures 1 through 3, with a battery orcollection of small exchangers. On the other hand, more than one drumcan be used with less heat exchangers. At the same time, installationsmay require that one exchanger be used with one drum. The variouscombinations of drums and. exchangers should fit the requirements of theparticular installation. For example, one drum can easily be used withonly one exchanger, or one drum can have more than one exchanger in theform of a battery or collection. At the same time, possibly two drumseither wet or dry, could be used with only one exchanger. In any event,all installations will require that at least one drum be used with oneexchanger.

Although I have not shown any specific superheater, it should beunderstood that one can easily be installed and used. For example, thesteam taken from the drum could be directed over another U-tube typeheat exchanger in contact with the coolant. Even though I have shownvalves between the heat exchangers and the drum and in the coolant linesleading to the heat exchangers in Figures 1 through 4, it should beunderstood that these can be eliminated, as in Figure 5, is desired.

While I have shown and described the preferred form and one modificationof my invention, it should be understood that numerous changes andalterations can be made without departing from the inventionsfundamental theme. I therefore wish that the invention be unrestrictedexcept as by the appended claims.

I claim:

1. In a steam generating system and the like, a water circuit and acoolant circuit, a plurality of generally upright elongated heatexchangers common to both the water and coolant circuits to effect heattransfer from the coolant to the water, each heat exchanger having apressure resistant bottom section with thickened walls for the coolantcapable of withstanding pressures on the order of 2300 pounds p. s. i.,and an upper elongated steam and water chamber with Walls substantiallythinner than those in' the bottom section, a thickened tube sheetbetween the bottom section and the upper chamber separating them, heatexchanger tubes connected to the tube sheet extending into the upperchamber, an inlet connection for the coolant connected to one portion ofthe bottom section of each heat exchanger, an outlet connection for thecoolant connected to another portion of the bottom section of each heatexchanger, the coolant inlet and outlet connections being constructedand arranged to provide coolant flow through the heat exchanger tubes, alongitudinal drum in the water circuit, a water return connectionbetween the bottom of the longitudinal drum and each of the heatexchangers connected generally at the bottom of the steam and waterchamber, a water outlet connection below the normal Water level for thesteam and water. chamber of. each heat exchanger recirculating Waterexternally to the bottomof the steam and water chamber, and a steamoutlet connection for. the top of the steam. and .water chamberofeachheat. exchanger connectedv to the drum.

2. The structure. of claim 1 in which. the. water. outlet connectionfor. the steam and water chamber for each heat exchanger is connected.to the longitudinal drum below its normal water level so that the wateris returned externally from the top to the bottom of the steam and waterchamber indirectly through the drum.

3. The structure of claim 1 in which the water outlet connection for thesteam and water chamber for each 5 heat exchanger is returned directlyto the bottom of the steam and water chamber.

References Cited in the file of this patent UNITED STATES PATENTS1,774,114 Vandeveer Aug. 26, 1930 1,781,057 Elmwall Nov. 11, 19302,220,045 Kraft et a1. Oct. 29, 1940 2,379,661 Sebald July 3, 1945

